Nutrition Practice Test Questions

In addition to the mentioned foods, legumes (including broad beans, pinto beans, and soybeans) are good sources of antioxidant vitamins and a variety of phytonutrients that often act as antioxidants, protecting the cells of the body from the damaging effect of free radicals.

Some of the best sources of antioxidants are berries, ginger, pomegranate, sunflower seeds, and walnuts.

Because many Americans under-consume fruits and vegetables, coffee is the top contributor to dietary polyphenols, providing ~40% of total polyphenols in US adults.

¹Journal of the Academy of Nutrition and Dietetics 120, no. 11

Although essential fatty acids are required for human metabolism, the body does not produce linoleic acid or α-Linolenic acid, and they must be derived from the diet.

Also known as polyunsaturated fatty acids, omega-3 and omega-6 fatty acids play vital roles in brain function as well as normal growth and development.

In addition to the above-mentioned facts, omega-3 fatty acids are necessary for the structure of cell membranes, especially in the brain and retina.

The cardioprotective effects of omega-3 fatty acids relate to improvements in blood pressure, cardiac function, and arterial and vascular function as well as improved lipid metabolism, antiplatelet, and anti-inflammatory effects.

Scurvy is caused by insufficient consumption of vitamin C. Although it is rare, older adults, persons who abuse alcohol, and those who eat a diet that does not contain fresh fruit and vegetables may be at risk of developing scurvy.

Along with the above-mentioned symptoms, persons with scurvy may suffer bleeding gums, petechial hemorrhage of the skin and mucous membranes, bleeding in the eye, and hyperkeratosis.

Coenzyme Q10 (CoQ10) is a fat-soluble quinone, a vitamin-like compound that is vital for activities related to energy metabolism.

CoQ10 is the coenzyme for at least three mitochondrial enzymes as well as enzymes in other parts of the cell and is involved in the key biochemical reactions that produce energy in cells. It also is a free radical scavenger and is metabolized to ubiquinol, which prolongs the antioxidant effect of vitamin E.

The highest amounts of it are found in the mitochondria of cells of organs with high-energy requirements such as the heart muscle, liver, kidneys, and pancreas.

Humans obtain vitamin D from two natural sources: sunlight and consumed food. Solar UVB radiation penetrates the skin and converts 7-dehydrocholesterol to previtamin D3, which is rapidly converted to vitamin D3.

Along with the above-mentioned foods, cod liver oil is a potent source of vitamin D and some orange juice, soy, and rice beverages are fortified with vitamin D.

Vitamin K1 is a cofactor needed for the synthesis of some of the substances that help blood to clot.

In adults, low dietary intake of vitamin K may be the result of chronic illness, malnutrition, alcoholism, multiple abdominal surgeries, long-term parenteral nutrition, malabsorption, gallbladder disease, liver disease, cystic fibrosis, inflammatory bowel disease, and long-term use of drugs such as antibiotics and cholestyramine, which binds to bile acids, preventing fat-soluble vitamin absorption.

Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. Mechanisms include competitive exclusion of pathogens, enhancing barrier function, and immune modulation.

Probiotics have been shown to relieve temporary abdominal bloating and to reduce intestinal gas.

Prebiotics are primarily oligosaccharides-short chains of sugar molecules that can only partially be digested. Most naturally occurring oligosaccharides are found in plants.

Prebiotics are often called bifidogenic factors because they primarily stimulate growth of bifidobacteria. Prebiotics work in concert with probiotics and have been found to produce many of the same health benefits.

Beriberi is rarely seen in the United States because many foods are fortified with thiamine.

Persons at risk of developing beriberi include those who abuse alcohol, persons on dialysis, and those taking high doses of diuretics as well as infants breastfed by mothers who lack sufficient thiamine.

Trigeminal neuralgia is characterized by sudden onset of severe pain that lasts less than a minute. It presents most commonly in persons age 50 and older and among women.

The frequency and severity of attacks recurs and remits, progressively worsening over time. While the disorder may be debilitating, it is not life threatening.

Tourette syndrome is characterized by tics, which are repetitive, involuntary behaviors, vocalizations, and movements such as eye blinking, grimacing and shrugging, or jerky muscle movements.

Tics also may include self-harm such as repetitively punching oneself as well as coprolalia and echolalia. Persons with Tourette syndrome frequently suffer behavioral problems such as hyperactivity, impulsivity, attention disorders, and repetitive behaviors.

The Dietary Guidelines for Americans (2020–2025) advise limiting added sugars to less than 10% of total daily calories for everyone ages 2 and older, and children under 2 should avoid added sugars entirely. Choosing nutrient-dense foods and swapping sugar-sweetened drinks and desserts for unsweetened options helps meet this target.

Dietary Guidelines for Americans (2020–2025)

In addition to the mentioned actions, niacin is a water-soluble vitamin that is necessary for cell respiration and supports the circulation, skin, nervous system, and secretion of bile.

Insufficient niacin intake is associated with symptoms such as canker sores, depression, fatigue, indigestion, weakness, skin problems, and inflammation. Chronic niacin deficiency is called pellagra.

The average American consumes about 50% more sodium than the 2,300 mg per day recommended in the Dietary Guidelines for Americans. Excessive sodium consumption is associated with increased risk for hypertension, which is associated with increased risk of developing cardiovascular disease.

Long-term inadequate intake of calcium is associated with low bone mass, rapid bone loss, and high risk of fracture.

In addition to the above-mentioned risk factors, chronic use of glucocorticoids, some anticonvulsants, inactivity, smoking, and changes in sex hormones such as amenorrhea, menopause, and low testosterone may increase the risk for osteoporosis.

Low-carbohydrate diets promote ketosis, the process of breaking down fat as opposed to carbohydrate to generate energy.

Ketones are acidic chemicals, which can build up in the blood and urine. Long-term very-low-carb/ketogenic patterns can have adverse effects and should be medically supervised.

Along with the mentioned characteristics, successful dieters monitor their weight, practice portion control, increase physical activity, and aim for healthy realistic weight loss ranging from 5%-10% of initial bodyweight over ~6 months. Successful dieters maintain their motivation by celebrating the achievement of weight-loss milestones.

In addition to the mentioned populations, supplemental iron may be given to treat anemia that occurs during pregnancy or as a result of heavy menstrual periods, kidney disease, or chemotherapy. Supplemental iron also may be recommended for vegetarians and women who are lactating. Iron requirements decrease for post-menopausal women.